Conveyer mechanism for folding carton blanks



June 3, 1952 A. w. LIEBL CONVEYER MECHANISM FOR FOLI-DING CARTON BLANKS2 SHEETSSHEET 1 Filed Sept. 4, 1948 ffiz/enl of'" dZAeri w. Liell @E LMI mv QM x MM RN N E A. W. LIEBL CONVEYER MECHANISM FOR FOLDING CARTONBLANKS June 3, 1952 v 2 SHEETS-SHEET 2 Filed Sept. 4, 1948 fnz/enior:QZAGT'Z U). Lie

Patented June 3, 1952 CONVEYER MECHANISM FOR FOLDING CARTON BLANKSAlbert W. Liebl, Philadelphia, Pa., assignor to Container Corporation ofAmerica, Chicago, 111., a corporation of Delaware Application September4, 1948, Serial No. 47,868

This invention relates, generally, to folding means, and it hasparticular relation to means for folding paperboard blanks that form,when set up, rectangular cartons.

Among the objects of this invention are: To fold sequentially the sidewalls of a paperboard blank, its front wall and then its back wall; toposition a plate in the path of the side walls to hold them folded; toposition a finger in the path of the front wall for folding the samebackwardly; to mount the finger rockably so that it can be moved out ofthe way of the leading edge of the bottom wall after the front wall hasbeen folded; to bias the front wall folding finger against suchmovement; to avoid the necessity for positively synchronizing theconveyor mechanism that moves the blank forwardly with the front andback wall folding mechanism; to move the front and back wall foldingmechanism forwardly by force transmitted through the blank; to mount thefront and back wall folding mechanism on an endless flexible cable, suchas a chain or belts, having a run paralleling the path of the bottomwall of the blank; to secure a lug on the cable to be engaged by theleading edge of the bottom wall of the blank for moving the cableforwardly and also to secure a folding finger on the cable arranged tofold over automatically the back wall of the blank; to mount the lug andfolding finger adjustably on the cable to accommodate blanks havingbottom walls of various lengths and widths; to employ a plurality ofsets of lugs and folding fingers on the cable, one or more sets for eachblank; and to provide duplicate endless flexible cables or chains forcarrying the sets of lugs and folding fingers in aligned relation.

Other objects of this invention will, in part, be obvious, and in partappear hereinafter.

This invention is disclosed in the embodiment thereof shown in theaccompanying drawings and it comprises the features of construction,combination of elements and arrangement of parts which will beexemplified in the construction hereinafter set forth and the scope ofthe application of which will be indicated in the appended claims.

For a more complete understanding of the nature and scope of thisinvention, reference can be had to the following description takentogether with the accompanying drawings, in which:

Figure l is a top plan view, somewhat diagrammatic in character, showinga folding means constructed in accordance with this invention;

15 Claims. (01. 9349) Figure 2 is a view, in side elevation and alsosomewhat diagrammatic in character, showing additional details of thefolding mechanism 11- lustrated in Figure 1;

Figures 3 and 4 are detail views illustrating how the front wall of theblank is folded over; and

Figures 5, 6 and 7 are perspective views of the paperboard blank invarious stages of the folding of the side, front and rear walls.

Referring now particularly to Figures 5, 6 and '7 of the drawings, itwill be observed that the reference character l0 designates, generally,

a paperboard blank having a bottom wall or panel ll, side walls or flapsl2 and a front wall or flap 13. As shown in Figure 5, the side walls orflaps 12 have been folded over the bottom wall or panel I I while thefront wall or flap l3 has yet to be folded over along a fold line orleading edge [4 of the bottom wall or panel II. The blank II) alsoincludes a back wall or flap l5 which is arranged to be folded along afold line or trailing edge I 6 of the bottom wall or panel II. It willbe understood that the side walls or flaps I2 first are folded as shownin these figures of the drawings. Next the front wall or flap- I3 isfolded over as indicated in Figure 6 and, finally, the back wall or flapi5 is folded over as indicated in Figure '7. The blank l0, as shown inFigure '7, can be packaged or stored in the folded condition and it isready to be set up to form a rectangular carton by moving the walls orflaps l2, I3 and i5 into positions at right angles to each other and tothe bottom wall or panel H. Suitable provision is made for interlockingthe corners of the carton when it is set up. For present purposes it isunnecessary to show these details since the present invention has to doparticularly with the manner in which the walls or flaps [2, I3 and I5are folded over the bottom wall or panel H to provide the folded blankas shown in Figure 7.

In order to fold the blank l0 in the manner just described, the foldingmechanism, shown generally at [9 in Figures 1 and 2 of the drawings, maybe employed. The folding mechanism [9 may constitute a separate machineor it may form a part of a gluing machine as may be desired. The foldingmechanism l9 includes side frame members 20 and 2| the supports forwhich are not shown in the drawings in order to simplify the disclosure.

The blank I0 is arranged to be moved from the right hand end of thefolding mechanism l9 as viewed in Figures 1 and 2 to theleft end bymeans of conveyor belts. These conveyor belts include a pair of bottomconveyor belts 22 which are trained at the left hand end over pulleys23. It will be understood that the underside of the bottom wall I Irests on the two bottom conveyor belts 22 and that it is ;movedforwardly thereby in: conjunction with arp'air of top conveyor belts 24.The top conveyor belts 24 are trained over pulleys 25 and 26 at theopposite ends. Also the top con: veyor belts 24 are trainedoverpulleys2' I, 2 8 29 and 30 which are arranged to direct the topcQi'i: veyor belts away from the corresponding-bottom conveyor belts 22for a portion pf'their travel so as to permit the front wall or flap.I'3tobe' folded over the bottom wall or panel II in a manner to bedescribed presently. Inpractice, suitably disposed guide pulleys (notshown) are provided for guiding the belts 24 onto the pulleys 21, as is.

known. A shown, the "top conveyor belts 24 are provided each Withja halftwist 3I between the -pulleys 2.5 and 2,'I for. the purpose of foldingthe sidewalls or fiaps' I2 over the bottom wall or panel II. In order toaccomplish that, the portions. of belts ,24'to the right, as viewed inFigure 1,

:of the :half twists, '3] thereof; are disposedoutward beyond belts 22,as are the pulleys 25, as

V will be :understoodfrom what has been said.

.i In some cases where the width ofcthe side walls or fiaps I2 .isrelatively, great, it may be desirable to provide forholding them inthefolded position over the bottom wall or panel II. For this purpose aplate 34 may be provided. As shdwn'in Figure 2, the plate "3.4 isinclined or "angu'l'arly disposed above the path of the'blank I 0 justafter the side walls or fiap's I2 have been "foIddbver by the halfLtwisted sections 3| of the top conveyor belts 24. The inclined plate 34may lieoin-itted where the belts-22 and24 are ofsufflcle'ht width so tohold the side Walls 01' flaps I12 in 'th'e' folded position.

With a view to folding over-thefront wall or iiap I3, there is providedafr'o'nt wall folder in form of an inverted L."-shap'ed finger'35. The

fr nt wall folder or -L sh'ap'e'd finger 35 is fast c w ereas which isjournaled at its ends in J p.158 31 that are carried by the side framemember ZIl and Zl. As shcwn in Figure 3, the

shaft 35 is provided withanarm as to which a coil tensionsprin'g 3S isattached. The spring 3L9 rates through the arm 38 to bias the frontwalljfolder or finger 35 to thepositionshown in Figure 2 of thedrawings. This construction perthe front wall folder or finger 315 to beswun to the finger 35. As a result of the continued forward movement ofthe bottom wall or panel I I of the blank I I], the finger 35 is swungin a clockwise direction to the position shown in Figure 4. The tensionof the spring 39 is sufficient to fold the front-wall or flap -I3;baclover the bottom W ll. or panel [I as 110??? i F r A150 the front wallfolder or finger 35 in this manner :is swung out of the path of theblank III which continues to 7 move forwardly.

As the blank III continues to move forwardly after the front wall orflap I3 has been folded QYQI' in themannerjust described, the leadingedge ;I4. engages -a pair of lugs 45 which may be 'adjiistablymounted'on a pair of endless flexible cables or chains .45,. It will be observedthat the cables or chains 45' are trained over sprockets 4laiid"48 andover an idler sprocket 49. The idler sprocket 49, as shown in Figure 2,is carried at the lower end of anadj-ustingarm which serves to maintainthe desired tension in the cables or chains 46.. It will be underst'oodthat the cables or chains 43are movedfforwardlysolely by forcetransmitted from the -'corive-yor.belts 22 and 24 through theblank IIIits engagement with the lugs' 45, In other words the cables or chains 46are not positively driven in synchronism with the ;c onveyor;belts 22and 2-4 other than in the manner-just described. I

The back wall or flap l of the blank I! is folded over asthe last step,iIL'the: processing .of the blank I0 through the folding mechanismls.For this purpose'a pair of folding fingers 5I is provided and they areadjustablyconnectedto the cables or chains 45. *The reason for-theadjustable connection of the foldi gfin ers SI as well as of the lugs 45is to permit the same apparatus to be empl'oyed'with blanks I5 havingdifferent lengths of bottom wens or panels II. The forward'ends 52 ofthe folding fingers 5I are-arranged to engag'e'theun'der side of theback'wall I5 and to swing it forwardly to theposition-shown in Figure'7. In order to accomplish this, the back end of "ea'ch'of the foldingfingers 5|; comprises a cam 53'. As "the foldingfingers -5I are swung bythe 'c'ables' or cliains'45 around the sprockets 41 the earns 53 "engagecollars 5B fastened theretoandas a result; the fingers 5! are'swungjfr'om'a position at right angles to the cables or chains 46 in'acounter clockwise direction. This movementisinustrated by the brokenline showing of one of the fingers 5I in Figure 2 as the cam 53 engagesthe collar 55 and moves 35 includes along arm 4 ll having a lower curvede'ndf4I which extends downwardly between the pair of bottom conveyorbelts 22 and. below the path. jof movement of. the bottom wall or panelI Ifo'f 'the bla nk ,IEL The curved lower end. 4 I is provided tofacilitate the engagement of the forwere (edge of the v front man 3 withthe front "wall folder. for finger 35. The spring 39, as shown in igure3, .is of sufiicient strength to hold the frontsw'all folder orfinger-35 in'th. position there shownfarid thus causes the front wallorflap I3 to be folded'along the. fold line or leading edge I4 as theblank I0 is moved forwardly by the conveyor belts ,2 2 and 24. Finally,,the forward ed e .of-the front wall or flap l3 engages. a short iar'm'42 or the riyehtwali glderorfih er 35 and thus is p'revented frommoving further relative the finger 5 I so that theforward ends52 engagethe under side ofthe back 'wan'or flap I5 and fold it overthe bottomwallor panel! I;'

Theforwardfoldihg-of the back wall or flap I5 is accomplished 'in partonly by the engagement of the cams 53 with the Collars 53'. The foldingoperation is completed by the engagement of the earns 53 With a track 51which extends between the co'nveyor belts zzahd 'za aha underneath. thepath of forward movemenrof the bottom wall or panel I'I andalso tangentto theperipheryof the Collar 56 Of each of th'sprcek'ets 41.

For purposes of description, the flaps I2 may be considered as sideflaps of the blank, and the flaps I3 and I5 may be considered as 'endflaps. In operation it will be understood that the blank-I8 the sameover the bottom wall or panel As will be understood, from what has beensaid, suitable hold down and feed means (not shown) is provided forfeeding the blanks forwardly be tween belts 22 and 24 as and for thepurpose stated. The hold down and feed means may be any suitable knownmeans such, for example, as that shown in the Staude et a1. Patent No.2,291,063. If the plate 34 is employed, it serves to hold the side wallsor flaps l2 in their folded positions. The blank I is moved forwardlyand the forward edge of the front wall or flap I3 engages the long arm40 of the front wall folder or finger 35 and slides upwardly along thesame until it engages the short arm 42. Thereafter the front wall orflap I3 is folded back as the leading edge H of the bottom wall or panelcontinues to move forwardly. At the same time the front wall folder orfinger 35 is swung in a clockwise direction as shown in Figure 4. Thisfolds the front wall or flap l3 back over the bottom wall or panel Afterthe blank ID has passed completely beyond the front wall folder orfinger 35, it swings back under the influence of the coil tension spring39 to the position shown in Figures 2 and 3 of the drawings. Bydirecting the top conveyor belts 24 over the pulleys 21, 28, 29 and 30it will be noted that sufficient space is provided for permitting thefront wall folder or finger 35 to function and to swing or fold thefront wall |3 over in the manner just described and for folding over theback wall l5.

'A suflicient number of pairs of lugs 45 are provided on the cables orchains 46 so that there always will be a pair ready to be engaged by theleading edge Id of the next blank 0. The uppermost run of the cables orchains 46 extends underneath the path of the bottom wall I I.

It will be understood that the pair of folding fingers associated withthe pair of lugs 45 engaged by the leading edge [4 of the blank H! arespaced therefrom sufficiently far to permit the bottom wall or panel IIto completely clear the same. The adjustment is such that the trailingedge I6 of the bottom wall or panel I is positioned just ahead of thepivot point of the folding fingers 5| and at the base of the curvedforward end 52 of the same. Then, as the fingers 5| are swung in acounter-clockwise direction by engagement of their cam ends 53 with thecollars 56, the curved forward ends 52 serve to fold the back wall |5over the bottom wall or panel while at the same time the blank I0continues to be moved forwardly. This folding operation performed on theback Wall or flap |5 is completed by engagement of the cam ends 53 withthe track 51 and the entering of its ends between the con veyor belts 22and 24.

Since certain changes can be made in the foregoing construction anddifferent embodiments of the invention can be made without departingfrom the spirit and scope thereof, it is intended that all matter shownin the accompanying drawings and described hereinbefore shall beinterpreted as illustrative and not in a limiting sense.

What is claimed as new is:

1. In a machine for folding the front and back walls relative to thebottom wall of a paperboard blank as it passes unidirectionallytherethrough to form ultimately a rectangular carton, in combination,conveyor means for moving the blank forwardly, a front wall folder inthe path of the forward movement of the blank for folding its front wallbackwardly relative to the bottom wall as it is moved forwardly, anendless flexible cable,

guide means directing said cable so that a portion thereof parallels thepath of the bottom wall, a lug secured to said cable and arranged to beengaged by the leading edge of the bottom wall with the front wallfolded back whereby said cable is moved in synchronism with the forwardmovement of the partially folded blank, a folding finger pivoted on saidcable at a distance from said lug determined by the length of the bottomwall, and cam means cooperating with said folding finger to rock itforwardly as the trailing edge of the bottom wall passes thereby forfolding the back wall forwardly relative to the bottom wall.

2. In amaohine for folding the front and back wallsrelative to thebottom wall of a paperboard blank as it passes unidirectionallytherethrough to form ultimately a rectangular carton, in combination,conveyor means for moving the blank forwardly, a front wall folder inthe form of an L-shaped finger with the long side arranged to be engagedby the leading edge of the front wall which slides therealong until itengages the short side to fold it backwardly relative to the bottom wallas the blank moves forwardly, support means for said finger rockablymounting it to swing about an axis transverse and parallel to themovement of the blank whereby it can be swung out of the path of theblank as the same is moved forwardly, spring means biasing said fingeragainst movement imparted thereto by the blank, an endless flexiblecable, guide means directing said cable so that a portion thereofparallels the path of the bottom wall, a lug secured to said cable andarranged to be engaged by the leading edge of the bottom wall with thefront wall folded back whereby said cable is moved in synchronism withthe forward movement of the partially folded blank, a folding fingerpivoted on said cable at a distance from said lug determined by thelength of the bottom wall, and cam means cooperating with said foldingfinger to rock it forwardly as the trailing edge of the bottom wallpasses thereby for folding the back wall forwardly relative to thebottom wall.

3. In a machine for folding the front and back walls relative to thebottom wall of a paperboard blank as it passes unidirectionallytherethrough to form ultimately a rectangular carton, in combination,conveyor means for movin the blank forwardly, a front wall folder in thepath of the forward movement of the blank for folding its front wallbackwardly relative to the bottom Wall as it is moved forwardly, anendless flexible cable, guide means directing said cable so that aportion thereof parallels the path of the bottom wall, a lug secured tosaid cable and arranged to be engaged by the leading edge of the bottomwall with the front wall folded back whereby said cable is moved insynchronism with the forward movement of the partially folded blank, afolding finger pivoted on said cable at a distance from said lugdetermined by the length of the bottom wall, the forward end of saidfolding finger being arranged to engage the back wall and the back endof said folding finger comprisin a cam, and abutment means positioned inthe path of said cam and engageable thereby to rock said folding fingerforwardly as the trailing edge of the bottom wall passes it for foldingthe back wall forwardly relative to the bottom wall.

4. In a machine for folding the front and back walls relative to thebottom wall of a paperboard 7- blank as-it'passes unidirectionally'therethrough to formaultimately a1 rectangular r'iar t'on'fin bination,conveyor. means .fornioving the blank forwardly, a frontwall folder intnefor nsr an L-shaped finger with the long, side arranged to be engagedby the leading edge of the front wall which slides therealong' until itvengages the short side to fold it backwardly relative to theibottomwall as the blank moves forwardly, support mean for said. fingerrockably mounting it to swing about an axis transverse and paralleltothe movement of the blank wherebyit can be swung out of the path of theblank as the same ismoved forwardly, spring means biasing said fingeragainst movement imparted thereto by the blank,

cable at a distance from-said lug determined b y the length ofthe'bottom wall, the forward end of said folding fingers being arrangedto engage the back wall and the back end of, said folding fingercomprising a. cam, and abutment means positioned. in the path of saidcam and-engageable thereby to rock said foldingfinger forwardly as thetrailing edge of the bottom wall. passesit for folding the back wallforwardlyrelative to the bottom wall. Y Y

5. In amachine forfolding the side, front and back walls relative to thebottom wall of apaperboard blank as it passes unidirectionallytherethrough to form ultimately a rectangular carton, in combination, apair of bottom carrierbeltsfor receiving the blank along the sides ofthe bottom wall, a. pair. ofvtop. carrier beltscooperating withsaidbottom belts to move thev blankposi tioned therebetween forwardly,each of i said top belts having a half twist therein as the blank entersbetween said bottom and top belts tofold theside walls over the bottomwall, a frontwall which said chain is trained so that a run thereofparallels the path of the bottom wall underneath the same and betweensaid bottom carrier. belts, a lug secured tov said chain and arranged tobe engaged by, the leading edge of the bottom wall with the front wallfolded back whereby said chain is moved in synchronism with the forwardmovement of the partially folded blank, a foldinglfinger pivoted on saidchain at a, distance from said lug, determined by the length of thebottom wall, and cam means cooperating with said folding finger torockit forwardly'as. the trailing edge of the bottom wall passes therebyfor foldingthe backiwall forwardly over. the bottom wall.

6. In a machine for folding the side, front and back walls relative tothe bottom wall of a paperboard blank as it passes unidirectionally.therethrough to form ultimately a rectangular carton, in combination, apair of bottom carrier. belts for receiving the blank along the sides.of the bottom wall, a pair of top. carrier belts cooperatingwith saidbottom belts to move the blank positioned therebetween forwardly, eachof said top belts having a half twist therein as the blank entersbetween said bottom and top belts to fold theside wallsiover the bottomwall, a front wall folder in the path'of the'forw ard'movement ofthe'blank for folding its front wall baokwardly over the bottom wan s itis o ed-f rw r y la e an ularly disposed above the path, of theblankbetween said half twists in said top belts andsaid front wall folder forengaging the folded: side walls to keep the same folded until the frontwall is folded over. their. forward ends, an, endless chain, front andrear sprocket over which said chain isv trained so that a run. thereofparallels the path of the. bottom wallunderneath the same and betweensaid bottom carrier belts,'a, lug se cured to said chain and arranged tobeengaged byfthe leading edge, of the bottom wall withthe front wallfolded back whereby said. chain is moved in synchronism with the forwardmove ment of the partially folded blank, a folding fins gerrpivoted onsaid chain at a distance from'seid lug determined by the length of thebottom wall, and cam means cooperating with said folding finger torockit forwardly as the trailing edge of the. bottom wallpasses thereby forfolding! the back wall forwardly over the bottom wall.

'7. In a machine, for folding the, side, frontand back walls relative tothebottom wall of a, paper:v board. blank as it passes. unidirectionallythere through to form ultimatelya rectangular carton, in combination, apair of bottom carrier belts for receiving the blank along: the sides ofthebottom wall, a pair of top carrier belts cooperating with said bottombelts to move the blank positioned therebetween forwardly; each of saidtop belts having a half twist therein as the blank enters between saidbottomandtop belts-to fold the side walls over the bottom wall; a frontWall folder-in the form of an L-shaped finger with the long sidearranged to be engaged'by the'leadingedge'of the front Wall which slidestherealong until it engages the short side to fold it backwardly over;the bot;- tom wall as the blank moves forwardly, support means for saidfinger rockably mounting itbetween said top belts to swing about anaxis-trans verse and parallel to the movement of the blank whereby itcan be swung out ofthe path of the blank as the same is moved forwardly,spring means biasing said finger. against movement-inrparted thereto bythe blank, an endless chain, front and rear sprockets over which saidchain is trained so that a run thereof parallels the path of the bottomwall underneath the same and between said bottom carrier belts a lugsecured to said chain and arranged to b'en'ga'ged-by the leading edge ofthe bottom wallwith the front wall folded back whereby said chain ismoved in synchronism with the forward'move ment'of the partially foldedblank, a folding finger-pivoted on said chain at a distance from saidlug determined by the length of the bottom wall, and cam meanscooperating with said folding finger to rock it forwardly as thetrailing edge of'the bottom wall passes thereby for folding the backwall forwardly over the bottom wall,

8. In a machine forv folding the side, front and back walls relative tothebottom wall ofi a paperboard blank as it passesunidirectionallythere; through to form ultimately a rectangular. carton,in combination, apair of bottomcarrier belt for receivingthe blank alongthe sides ofthe bottom wall, a pair of top carrier belts cooperating,with said bottom belts to move the blank positioned therebetweenforwardly, each of said top belts having. a half .twist therein as theblank: enters between said bottom and top belts tofoldithe side wallsover the bottom wall, a front wall folder in the'path of the forwardmovement ofrthe' blank for foldingits frontwall backwardly over thebottom wall as it ismoved forwardly, an endless chain, front and rearsprockets over which said chain is trained so that a run thereofparallels the path of the bottom wall underneath the same and betweensaid bottom carrier belts, a lug secured to saidchain and arranged to beengaged by the leading edge of the bottom'wall with the front wallfolded back whereby said'chain is moved in synchronism with the forwardmovement of the partially folded blank, a folding finger pivoted on saidchain at a distance from said lug determined by the length of the bottomwall, cam means cooperating with said folding; finger to rockit.forwardly as the trailing edge of the bottom wall passes thereby forfolding the back wall forwardly over the bottom Wall, and pulleys overwhich each of said top belts is trained to direct each ofthem away fromand back toward said bottom belts to provide a space where the front andback walls can be folded as aforesaid.

9. In a machine for folding the side, front and back walls relative tothe bottom wall of a paperboard blank as it passes unidirectionallytherethrough to form ultimately a rectangular carton, in combination, apair of bottom carrier belts for receiving the blank along the sides ofthe bottom wall, a pair of top carrier belts cooperating with saidbottom belts to move the blank positioned therebetween forwardly, eachof said top belts having a half twist therein as the blank entersbetween said bottom and top belts to fold the side walls over the bottomwall, a front wall folder in the path of the forward movement of theblank for folding its front wall backwardly over the bottom wall as itis moved forwardly, an endless chain, front and rear sprockets overwhich said chain is trained so that a run thereof parallels the path ofthe bottom wall underneath the same and between said bottom carrierbelts, a lug secured to said chain and arranged to be engaged by theleading edge of the bottom wall with the front wall folded back wherebysaid chain is moved in synchronism with the forward movement of thepartially folded blank, a folding finger pivoted on said chain at adistance from said lug determined by the length of the bottom wall, theforward end of said folding finger being arranged to engage the backwall and the back end of said folding finger comprising a cam, andabutment means positioned in the path of said cam and. engageablethereby to rock said folding finger forwardly as the trailing edge ofthe bottom wall passes it for folding the back wall forwardly over thebottom wall.

10. In a machine for folding the side, front and back walls relative tothe bottom wall of a paperboard blank as it passes unidirectionallytherethrough to form ultimately a rectangular carton, in combination, apair of bottom carrier belts for receiving the blank along the sides ofthe bottom wall, a pair of top carrier belts cooperating with saidbottom belts to move the blank position therebetween forwardly, each ofsaid top belts having a half twist therein as the blank enters betweensaid bottom and top belts to fold the side walls over the bottom wall, afront wall folder in the path of the forward movement of the blank forfolding its front wall backwardly over the bottom wall as it is movedforwardly, an endless chain, front and rear sprockets over which saidchain is trained so that a run thereof parallels the path of the bottomwall underneath the same and between-said bottom carrier belts, a lugsecured to said chain and arranged to be. engaged by the leading edge ofthe bottom wall with the front wall folded back whereby said chain ismoved in synchronism with the forward movement of the partially foldedblank, a folding finger pivoted on said chain at a distance, from saidlug determined by thelength of the bottomwall, the forward end of saidfolding finger being arranged to engage the back wall and the back endof said folding finger comprising 'a cam, and a circular flange on saidrear sprocket positioned in the path of said cam and engageable therebyto rock said folding finger forwardly as the trailing edge of the bottomwall passes it for folding the back wall forwardly over the bottom wall.a Y

llwlna machine for folding the sid'e,-front and back walls relative tothe bottom wallof a paperboard blank. as. it passes unidirectionallytherethrough to form ultimately a rectangularc'arton, in combination, apair of bottom carrier belts for receiving the blank along the sidesofthe bottom wall, a pair of top carrier belts 00- operating with saidbottom belts to move the blank positioned therebetween forwardly, eachof said top belts having a half twist therein as the blank entersbetween said bottom and top belts to fold the side walls over the bottomwall, a front wall folder in the path of the forward movement of theblank for folding its front wall backwardly over the bottom wall as itis moved forwardly, an endless chain, front and rear sprockets overwhich said chain is trained so that a run thereof parallels the path ofthe bottom wall underneath the sam and between said bottom carrierbelts, a lug secured to said chain and arranged to be engaged by theleading edge of the bottom wall with the front wall folded back wherebysaid chain is moved in synchronism with the forward movement of thepartially folded blank, a folding finger pivoted on said chain at adistance from said lug determined by the length of the bottom wall, theforward end of said fold- 1ng finger being arranged to engage the backwall and the back end of said folding finger comprising a cam, acircular flange on said rear sprocket positioned in the path of said camand engageable thereby to rock said folding finger forwardly as thetrailing edge of the bottom Wall passes it for folding the back wallforwardly over the bottom wall, and a track tangent to said circularflange and engageable by said cam after it leaves the same for holdingthe back wall in the folded position as the blank is moved forwardly bysaid top and bottom belts.

12. The invention, as set forth in claim 5, wherein a plurality of setsof lugs and folding fingers ar carried by the chain so spaced that thelug of the next set is advanced into position for engagement by theforward edge of the bottom wall of the next blank as a result of theengagement of the preceding lug by the preceding blank.

13. The invention, as set forth in claim 12, wherein two chains areemployed each having a plurality of sets of lugs and folding fingerscarried thereby and positioned so that the forward edge of the bottomwall of the blank engages simultaneously a lug on each chain and thecorresponding folding fingers act simultaneously to fold over its backwall.

14. In a machine for folding blanks having a bottom panel and end flapsconnected to said panel along fold lines, means for advancing the blanksalong a rectilineal path of travel, means.

amusing the leading: endflap of the blank toward-Jsaidpanel in thetravel of the blank, an endless belt having ;a run paralleling the pathof travel of the-:blanks and driven thereby, abutmentson said beltdisposed to be contacted by 3 the;,l e ading edges of the blanksiordriving saidriedflby said belt disposed and adapted to fold thefollowing;end flap of the respective blanks toward-thebottqm panelthereof in the continued travelof said blank and the travel therewith ofaid e t-i r 15. In a machine for folding blanks having-a bottom -paneliand side and. end .flaps connected to said-panelralong foldflines,means :foradvanchgathe; blanks along, a rectilineal. path' of traveland; folding said side flapsvand the: leading end flap-ztoward saidpanel, an endless belt having a runrparallelingithe path of travel ofthe blanks and driven-thereby, abutments on said belt-disposed; andadapted to receive and becontacted by'the leading end portion of theblanks fo'r driving said belt in the advancement of said blanks, contactof the moving .blanks with said abutments providing the sole means fordriving said belt, cam means, and folding fingers cooperating with saidcam means disposed and adapted'to fold the following end flap of 'therespective' blanks towardthe bottom panel thereof in the continuedtravel of said blank and thetravel therewith of said'belt.

ALBERT W. LIE-BL;

REFERENCES ci'rE-D Thefollowing-reference's are of record inthe" file ofthis patent:

UNITED? STATES PATENTS

